Multiple levels of control in the Stroop task

Multiple levels of control may be used in service of reducing Stroop interference. One is list-wide, whereby interference is reduced strategically in lists that include disproportionately more incongruent trials. A second, item-specific control is observed when proportion congruence is manipulated at the level of items. Item-specific control reduces interference for mostly incongruent relative to mostly congruent items. First, we show that item-specific control may drive both list-wide and item-specific proportion congruence effects (Experiment 1). We then show that item-specific control affects Stroop interference similarly when a single feature (a word) as opposed to a feature combination (a word 1 font type) signals proportion congruence (Experiment 2). Although this suggests that font type offers little advantage for controlling Stroop interference beyond the word, a novel, font-specific proportion congruence effect is observed in Experiment 3, indicating that font type can be used to control interference. These findings support the idea that multiple levels of control are used in reducing Stroop interference.     

Transfer of location-specific control to untrained locations

Recent research highlights a seemingly flexible and automatic form of cognitive control that is triggered by potent contextual cues, as exemplified by the location-specific proportion congruence effect--reduced compatibility effects in locations associated with a high as compared to low likelihood of conflict. We investigated just how flexible location-specific control is by examining whether novel locations effectively cue control for congruency-unbiased stimuli. In two experiments, biased (mostly compatible or mostly incompatible) training stimuli appeared in distinct locations. During a final block, unbiased (50% compatible) stimuli appeared in novel untrained locations spatially linked to biased locations. The flanker compatibly effect was reduced for unbiased stimuli in novel locations linked to a mostly incompatible compared to a mostly compatible location, indicating transfer. Transfer was observed when stimuli appeared along a linear function (Experiment 1) or in rings of a bullseye (Experiment 2). The novel transfer effects imply that location-specific control is more flexible than previously reported and further counter the complex stimulus–response learning account of location-specific proportion congruence effects. We propose that the representation and retrieval of control settings in untrained locations may depend on environmental support and the presentation of stimuli in novel locations that fall within the same categories of space as trained locations.     

Can the survival recall advantage be explained by basic memory processes?

Nairne, Thompson, and Pandeirada (2007) demonstrated a striking phenomenon: Words rated for relevance to a grasslands survival scenario were remembered better than identical words encoded under other deep processing conditions. Having replicated this effect using a novel set of words (Experiment 1), we contrasted the schematic processing and evolutionary accounts of the recall advantage (Experiment 2). Inconsistent with the schematic processing account, the grasslands survival scenario produced better recall than did a city survival scenario requiring comparable schematic processing. Recall in the grasslands scenario was unaffected by a self-reference manipulation. The findings are consistent with an evolutionary account that attributes the recall advantage to adaptive memory biases.     

P50 sensory gating is related to performance on select tasks of cognitive inhibition

P50 suppression deficits have been documented in clinical and nonclinical populations, but the behavioral correlates of impaired auditory sensory gating remain poorly understood. In the present study, we examined the relationship between P50 gating and healthy adults’ performance on cognitive inhibition tasks. On the basis of load theory (Lavie, Hirst, de Fockert, & Viding, 2004), we predicted that a high perceptual load, a possible consequence of poor auditory P50 sensory gating, would have differential (i.e., positive vs. negative) effects on performance of cognitive inhibition tasks. A dissociation was observed such that P50 gating was negatively related to interference resolution on a Stroop task and positively related to response inhibition on a go/no-go task. Our findings support the idea that a high perceptual load may be beneficial to Stroop performance because of the reduced processing of distractors but detrimental to performance on the go/no-go task because of interference with stimulus discrimination.     

Repetition Errors in Habitual Prospective Memory: Elimination of Age Differences via Complex Actions or Appropriate Resource Allocation

ABSTRACT

A challenge in habitual prospective memory tasks (e.g., taking medication) is remembering whether or not one has already performed the action. Einstein, McDaniel, Smith, and Shaw (1998 Einstein, G. O., McDaniel, M. A., Smith, R. E. and Shaw, P. 1998. Habitual prospective memory and aging: Remembering intentions and forgetting actions. Psychological Science, 9: 284–288. [Crossref], [Web of Science ®] , [Google Scholar], Psychological Science, 9, 284) showed that older adults were more likely to incorrectly repeat an action on habitual prospective memory tasks. Extending this research, we (a) biased participants either toward repetition or omission errors, (b) investigated whether performing a more complicated motor action can reduce repetition errors for older adults, and (c) examined participants' resource allocation to the prospective memory task. Older adults committed more repetition errors than younger adults regardless of biasing instructions when ongoing task demands were challenging (Experiment 1). Performing the more complex motor action, however, reduced repetition errors for older adults. Further, when the ongoing task was less demanding, older adults' repetition errors declined to levels of younger adults (Experiment 2). Consistent with this finding, the resource allocation profiles suggested that older participants were monitoring their output (prospective memory execution) in each trial block.     

Facial expressions of pain in muscle-contraction headache patients

Using a judgment and component analysis of facial actions, 14 muscle-contraction headache (MCH) patients were videotaped in headache and nonheadache states. In addition, patients were also required to undergo a resting physiological assessment (frontalis electromyography, temporal blood volume pulse, and heart rate), reaction-time task, and complete self-report measures of pain state and mood. Headache and nonheadache state of MCH patients were reliably identified by 20 observers. Characteristics of facial expressions that occurred most frequently in the headache state included furrowed eyebrows, closed eyes, slow eye blinks, lip pursuing, facial grimacing, and flat facial affect. Headache state was also associated with increased latency to respond to an auditory tone and mood disturbances, but no differences in baseline physiological activity were observed. Our findings provide support for the utility and clinical relevance of judgment and component analysis of facial actions in MCH patients.     

The next trial will be conflicting! Effects of explicit congruency pre-cues on cognitive control

The dual mechanisms of control account proposed a role for proactive and reactive mechanisms in minimizing or resolving interference in conflict tasks. Proactive mechanisms are activated in advance of stimulus onset and lead to preparatory biasing of attention in a goal-directed fashion. Reactive mechanisms are triggered post-stimulus onset. Using an explicit, trial-by-trial pre-cueing procedure in a 4-choice color-word Stroop task, we investigated effects of congruency pre-cues on cognitive control. Under conditions of stimulus uncertainty (i.e., each word was associated with multiple, equally probable responses), pre-cue benefits were observed on incongruent trials when cues were 100 % valid but not when they were 75 % valid. These benefits were selectively found at the longest cue-to-stimulus interval (2,000 ms), consistent with a preparation-dependent proactive control mechanism. By contrast, when a reactive strategy of switching attention to the irrelevant dimension to predict the single correlated response was viable, pre-cue benefits were observed on incongruent trials for all cue-to-stimulus intervals including the shortest that afforded only 500 ms to prepare. The findings (a) suggest a restricted role for the preparation-dependent biasing of attention via proactive control in response to explicit, trial-by-trial pre-cues while (b) highlighting strategies that lead to pre-cue benefits but which appear to reflect primarily reactive use of the information afforded by the pre-cues. We conclude that pre-cues, though available in advance of stimulus onset, may stimulate proactive or reactive minimization of interference.